BACKPORT, FROMGIT: crypto: speck - add test vectors for Speck64-XTS

BACKPORT, FROMGIT: crypto: speck - add test vectors for Speck64-XTS

Add test vectors for Speck64-XTS, generated in userspace using C code.
The inputs were borrowed from the AES-XTS test vectors, with key lengths
adjusted.

xts-speck64-neon passes these tests.  However, they aren't currently
applicable for the generic XTS template, as that only supports a 128-bit
block size.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit 41b3316e75ee5e8aec7234c9d631582b13a38c7d
 git://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master)
(removed 'const' from test vectors)
(replaced use of __VECS macro in crypto/testmgr.c)
Change-Id: I61a2c77dbfcf487d77b3d9ef0a823dadea8ddf07
Signed-off-by: Eric Biggers <ebiggers@google.com>